The present invention relates to an apparatus in a paper or cardboard machine as defined in the preamble of claim 1 for confining the pulp flow from the headbox, said apparatus comprising at least one deckle system, which comprises a deckle part and supporting elements supporting the deckle part, said deckle part being so arranged that the deckle part in its service position confines the pulp flow from the headbox in the sideways direction in the edge area of the wire.
The apparatus forming the object of the invention is typically referred to as a deckle. Its function is to contain the flow of stock discharged from the headbox slice onto the wire so as to confine the flow in the sideways direction at the edges of the wire. Thus, the aim is to prevent uncontrolled spreading of stock on the wire immediately after the headbox. After the stock has advanced through some distance on the wire in the machine direction and a sufficient amount of water has been removed from it, this problem disappears. A common method of confining the flow of stock in the sideways direction is to use deckles at the edges of the wire immediately after the headbox.
Deckles typically consist of a deckle part and a mechanism supporting it. The deckle part of deckles is traditionally supported by suspending it from above. This involves certain drawbacks, including the fact that during operation the deckle part can be rotated about an axis parallel to the longitudinal direction of the machine due to the pulp pressure, especially with large headbox slice values. In addition, the thermal stress has the effect that the deckle, as seen from above, is bent in the transverse direction of the machine. As a consequence of this, the deckle produces so-called undulations at the edges of the stock web and the web becomes thinner in the edge area due to pulp loss. Traditionally, the deckle end adjacent to the headbox has been provided with adjustments both in a vertical direction and in the longitudinal direction of the machine. After maintenance and a wire change, connecting these fixtures has proved to be a laborious task and the adjustment settings of the deckle in the transverse direction of the machine and in the vertical direction have changed.
Traditional deckle mounting solutions have thus been complicated and/or difficult to adjust. This is a problem especially in conjunction with maintenance and wire changes, because connecting the deckle mounting elements has proved to be a laborious task and additionally the adjustment settings of the deckles in the transverse direction of the machine and in the vertical direction may have changed. Therefore, setting the deckles back to the position in which they were before the maintenance operations is difficult and time-consuming.
The object of the present invention is to achieve a completely new type of solution that will allow problems of prior art to be avoided. Thus, the object of the invention is to create a sturdy deckle solution that can be easily removed from the service position e.g. in connection with maintenance activities or wire changes and returned back to its former position after the maintenance. A further object is to create a deckle mounting solution that fulfills corresponding objectives.